This conference paper (recently added to NTRS collection) addresses a method of reducing the effects of debris rather than detection methods - thought it might be of interest to readers of this thread.

The potential to perturb debris orbits using photon pressure from ground-based lasers has been confirmed by independent research teams. Two useful applications of this scheme are protecting space assets from impacts with debris and stabilizing the orbital debris environment, both relying on collision avoidance rather than de-orbiting debris. This paper presents the results of a new assessment method to analyze the efficiency of the concept for collision avoidance. Earlier research concluded that one ground based system consisting of a 10 kW class laser, directed by a 1.5 m telescope with adaptive optics, can prevent a significant fraction of debris-debris collisions in low Earth orbit. That research used in-track displacement to measure efficiency and restricted itself to an analysis of a limited number of objects. As orbit prediction error is dependent on debris object properties, a static displacement threshold should be complemented with another measure to assess the efficiency of the scheme. In this paper we present the results of an approach using probability of collision. Using a least-squares fitting method, we improve the quality of the original TLE catalogue in terms of state and co-state accuracy. We then calculate collision probabilities for all the objects in the catalogue. The conjunctions with the highest risk of collision are then engaged by a simulated network of laser ground stations. After those engagements, the perturbed orbits are used to re-assess the collision probability in a 20 minute window around the original conjunction. We then use different criteria to evaluate the utility of the laser-based collision avoidance scheme and assess the number of base-line ground stations needed to mitigate a significant number of high probability conjunctions. Finally, we also give an account how a laser ground station can be used for both orbit deflection and debris tracking.

Conclusions

We investigated the efficiency of the LightForce photon pressure collision avoidance concept using the entire catalogue of tracked space objects. We assembled a list of occurring conjunctions for the simulation time frame, investigated the utility of several different LightForce configurations and developed two different metrics to assess the utility of the system. The first metric is used to assess the fraction of conjunctions that can be mitigated. This approach is useful if one wants to optimize for the protection of assets, e.g. gain the capability to protect one satellite against as many potential impacts as possible. The second metric assesses the reduction of the expected value of collisions if the system is active. This metric is useful for optimizing the effect on the debris environment in general. LightForce can be used to achieve both goals. With one 20 kW laser placed in Antarctica, a fraction of 58% of conjunctions can be mitigated, resulting in 79% reduction in expected number of collisions (for now neglecting effects of station duty cycles). More sophisticated systems improve those numbers (see Tables 3,4). These results illustrate why we believe that LightForce is a suitable solution to provide immediate benefits for space operations and also would be an extremely beneficial supplement to any long-term active debris removal efforts.

Figure 1 Caption:Schematic view of a laser facility and the operations for nudging space debris using photon pressure. Slowing down the debris results in loss in orbital energy, hence in a lower orbit with a higher velocity.

Story at a Glance• Ground breaking kicks off a 36-month long construction effort to build the Space Fence radar system on Kwajalein Atoll• Space Fence will significantly improve space situational awareness by more accurately detecting and tracking objects such as satellites,space debris• Once complete, the Air Force will conduct system acceptance testing• Projected date for the system's initial operational capability is January 2019

3/17/2015 - U.S. ARMY GARRISON- KWAJALEIN ATOLL, Republic of the Marshall Islands - -- Officials from the U.S. Air Force Space and Missile Systems Center and Lockheed Martin's Mission Systems and Training recently participated in a formal ground breaking ceremony on Kwajalein Atoll to kick off a 36-month long construction effort to build the Space Fence radar system. The ceremony was held, Feb. 10.

Space Fence is designed to provide assured coverage at Low Earth Orbit for objects as small as 10 centimeters. The system will also support cued searches and uncued surveillance at Medium Earth Orbit and above. The increased Space Fence sensitivity, coupled with the improved computing capabilities of the JSpOC Mission System, will yield a greater understanding of the space operating environment and its associated threats.

"The Air Force is pleased to partner with Lockheed Martin in providing a system that will transform how we view the space operational environment," said David Madden, SMC's executive director.

Space Fence will significantly improve space situational awareness by more accurately detecting and tracking objects such as commercial and military satellites and space debris. "Space is becoming more congested and contested so it is critical that we deliver this system on time and on schedule," Madden said.

The Air Force Life Cycle Management Center, located at Hanscon AFB, Mass. awarded the engineering, manufacturing and design contract valued at $914 million to Lockheed Martin on June 2, 2014. Lockheed Martin and their subcontractors AMEC, GDST, Merrimac Industries, Wolf Creek and San Juan Construction will be working on Kwajalein with activities ranging from power generation, communications and radome installation and facility construction. Approximately 250 workers will live on the island during construction.

Once the construction is complete, the Air Force will conduct system acceptance testing. The projected date for the system's initial operational capability is January 2019.

« Last Edit: 03/18/2015 07:15 AM by Targeteer »

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Best quote heard during an inspection, "I was unaware that I was the only one who was aware."

MOORESTOWN, N.J., Sept. 28, 2015 – Lockheed Martin’s (NYSE: LMT) Space Fence System, including the large-scale digital radar and turn-key facility were deemed technically mature and provided evidence that all requirements will be met through the program’s Critical Design Review (CDR) conducted by the U.S. Air Force.Government representatives met with Lockheed Martin engineers in Moorestown to review the Space Fence S-band radar system design, which will detect, track, and catalog orbital objects in space more than 1.5 million times a day to predict and prevent space-based collisions. The three-day CDR was preceded by the delivery of 21,000 pages of design documents, and an eight-day Design Walkthrough, to ensure the system will meet performance requirements. The CDR event featured the demonstration of a small-scale system built with end-item components that detected and tracked orbiting space objects.“Completion of CDR marks the end of the design phase and the start of radar production and facility construction of the Space Fence system,” says Steve Bruce, vice president for Advanced Systems at Lockheed Martin’s Mission Systems and Training business. "Once complete, Space Fence will deliver revolutionary capability to the U.S. Air Force with a flexible system capable of adapting to future missions requiring new tracking and coverage approaches. We look forward to continuing our successful partnerships with the U.S. Air Force Space and Missile Systems Center, Life-Cycle Management Center and Space Command.”Within the Space Fence radar open architecture design, Lockheed Martin uses the latest monolithic microwave integrated circuit technology, including Gallium Nitride (GaN) semiconductor materials. GaN provides a number of significant advantages for active phased array radar systems, including higher power density, greater efficiency and significantly improved reliability over previous technologies.Lockheed Martin has a decade of investment and significant experience in successfully developing GaN-based products. Lockheed Martin is able to procure mature technology that is commercially available, aided by significant investment occurring in the marketplace in areas such as cell phone infrastructure and LED design. This is in alignment with the recent release of Better Buying power 3.0 and the need to leverage commercial technology where applicable to lower development costs and provide greater value for the Department of Defense.In addition to engineering the radar arrays, the Lockheed Martin team also broke ground on the new six-acre Space Fence site earlier this year on Kwajalein Island, 2,100 miles southwest of Honolulu. The construction process is challenging due to the remoteness and cultural and historic significance of the location. The buildings are designed to handle high winds and seismic loads, while maintaining the alignment and accuracy of the radar system.The sensor site installation will include an on-site operations center and an annex to the current island power plant that will ensure the Space Fence system has everything necessary to provide continuous Space Situational Awareness. Once construction is complete, Space Fence will go through testing and validation before its initial operating capability occurs in late 2018.For additional information, visit our website: www.lockheedmartin.com/spacefence.About Lockheed MartinHeadquartered in Bethesda, Maryland, Lockheed Martin is a global security and aerospace company that employs approximately 112,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services. The Corporation’s net sales for 2014 were $45.6 billion.

WASHINGTON – Lockheed Martin has built a scaled-down version of the U.S. Air Force’s next-generation space surveillance system in New Jersey as a way to test hardware and software for the Space Fence, the company announced March 28.

A long-awaited update to the hardware and software system that will allow the U.S. Air Force to ingest data from its new object tracking system, known as Space Fence, will not be ready until 2018, about 19 months later than previous estimates, an Air Force spokeswoman said April 11.

The Air Force has been undergoing a broad modernization of the Joint Space Operations Center (JSpOC), the processing center of U.S. military space operations headquartered at Vandenberg Air Force Base, California.

The program, known as the JSpOC Mission System (JMS), is a three-phased, $1 billion initiative to replace or upgrade the hardware and software currently used for space surveillance, collision avoidance, launch support, and providing more precise and timely orbital information. The new system replaces the legacy Space Defense Operations Center, or SPADOC, which Air Force officials say is dated and becoming increasingly difficult to maintain.

While dodging debris is an improvement over not dodging it, is there any effort or plan or even hint of a plan to actually begin debris clean-up? I suspect that we'll be true to form and wait until we are in the full crisis mode -- Kessler cascade has begun -- before we start a crash (no pun intended) program to fix it.

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"If we shared everything [we are working on] people would think we are insane!"-- SpaceX friend of mlindner

While dodging debris is an improvement over not dodging it, is there any effort or plan or even hint of a plan to actually begin debris clean-up? I suspect that we'll be true to form and wait until we are in the full crisis mode -- Kessler cascade has begun -- before we start a crash (no pun intended) program to fix it.

so far just talk and endless powerPoint development but everyone is so far to scared to make the first move to actually act on the present data. The keep prodding other to make the first move but no one is budging except those that want to do ASAT testing as the contribution.

​Colorado Springs, Colo.—The head of Air Force Space Command would prefer to have airmen who are doing collision avoidance and orbital analysis focus on other missions, but the military must continue to operate the network for “space control,” AFSPC boss Gen. John Hyten said. The FAA and Rep. Jim Bridenstine (R-Okla.) both recently proposed moving space traffic management tracking from the Air Force to the Federal Aviation Administration, and Hyten said he is “good with” providing data to the FAA and having them “do the math” on collision avoidance. But, he said, the commercial sector will “never have a capability as good as the space fence,” which cost $914 million and will increase the number of objects USAF tracks in space by tenfold. So, Hyten said, there are some details to work through with the FAA to make sure it’s all done right, but “the vision is correct: We shouldn’t be doing flight safety for everybody in the world.”